Piston



' July 10, 1928.

T. J. LEVEY PISTON s Sheets-Sheet Filed April 15, 1926 INVENTOR 27208. J Levey BY A TT ORNE Y July 10, 1928. 1,676,339

v T. J. LEYEY PISTON File April 192s 5 Sheets-Sheet 2 INVEOR T/zoa J Lea/ BY ATTORNEY v T. J. LEVEY July 10, 1928.

PISTON Filed April 1926 3 Sheets-Sheet 3 INVENTOR 'Thay. J 1, 6065/ TTORNEY Patented July 10, 1928.

UNITED STATES PATENT oFFicE.

PISTON.

4 Application filed April 13,

This invention relates to pistons and has for its object to provide a construction more efficient in use than those heretofore proposed.

With this and other objects in view, the invention consists in the novel details of construction and combinations of parts as will be more fully hereinafter disclosed and particularly pointed out in the claims.

Referring to the accompanying drawin forming a part of this specification, in whic like numerals designate like parts in all the views Fig. 1 is a side elevational view partly in section of a device made in accordance with this invention;

Fig-2 is a vertical sectional view taken on the line 2-2 of Fig. 1 and looking in the direction of the arrows;

Fig. 3 is a view similar to Fig. 1 illustrating a slight modification of the invention.

Fig. 4 is a view similar to Fig. 1 of a still further modified form of the invention.

Fig. 5 is a transverse sectional view taken on the line 5-5 of Fig. 1 and looking in the direction of the arrows;

Fig. 6 is a transverse sectional view taken on the line 6-6 of Fig. 1 and looking in the directionof the arrows;

-Fig. 7 is a transverse sectional view taken on the line 77 of Fig. 3 and looking in the direction of the arrows;

Fig. 8 is a perspective view of the expansive skirt portion of the piston illustrated in Fig. 1;

Fig. 9 is a partial perspective view similar to Fig. 8 illustrating. the expansive skirt portion of the piston. illustrated in Fig. 3;

Fig, 10 is a plan view of one of the spring rings associated with the expansive skirt portion of the piston;

Fig. 11 is a vertical sectional View of an engine cylinder illustrating the action of the engine crank shaft and connections on a piston of the usual construction in said cylinder; and

Fig. 12 is a view similar to Fig. 11 illustrating the action of the engine crank shaft and connections on a piston made in accordance with this invention and applied to an engine cylinder. I

1 indicates generally a piston provided with the usual head portion 2, annular grooves 3 for the reception of the usual 1926. Serial no. 101,757.

packing rings 4 which may be of any suitable or well known construction. The main body portion ofthe piston, generally indicated by the numeral 5, has the usual inwardly formed bosses6 forming the bearings for the wrist pin 7 (see Fig. 11) which ]OlIlS the piston 1 to its 'pitman or connecting link 8 which in turn is secured as by the collar or other fastening device 9 to the bearing 10 on the engine crank 11.

The exterior surface of the main body portion 5 of the piston (see Fig. 2) is reduced in diameter below the region where the rings 4 are located to provide the upper shoulder 15, the lower shoulder 16, an the surface 17 all as clearly indicated in the drawings. In addition to this there is formed in the surface 17 an upper annular groove 18 and a lower annular groove 19 adapted to receive the spring rings 20. With particular reference to Fig. 1 it will be observed that the exterior surface of the main body portion 5 adjacent each wrist pin bore22 is sunk below the spring ring grooves 18 and 19 to form the recess or depression 23 for a purpose that will appear later. Through the wall of the main body portion 5 of the piston between the annular grooves 18 and 19, there is provided a plurality of obliquely disposed apertures or slits 25, the upper end of each slit verti- .85 cally overlapping the lower end of the next adjacent slit, all as clearly shown in Fig. 2 for a purpose presently to appear.

With particular reference to Fig. 10 illus tratingone of the spring rings 20, it will be observed that said ring is made substantially polygonal in shape, the periphery being made up of a plurality of inwardly curved arcuate sections 30 and outwardly projecting rounded points 31. When the ring 20 is applied to either of the ooves therefor, it will be obvious that said ring will not contact with the entire surface of the groove. In other words, the only portions of the ring which will be in contact with said groove will be the innermost portion 32 of each of the arcuate sections 30 and also it will be obvious that any pressure brought to bear on the outwardly extending points 31 of said ring, will cause a spring action in each of said sections forming the ring 20 with the resultant tendency to have said ring assume more nearly a truly circular shape, thus bringing the extreme ends 33 of said ring closer together. It is to be understood of course that each of the spring rings 20 is to be made of any suitable metal having a spring quality similar to steel and suitable for the use and temperature to which they are put, and that each ring will snugly fit its groove when placed therein.

Referring particularly to Figs. 1 and 8, there is disclosed an outer expansive skirt portion, generally indicated by the numeral 35,'forming a part of the piston. This skirt portion is formed from a relatively wide thin band of light weightmetal such as aluminum or an alloy thereof whose two ends are bent around producing the circular formation shown in Fig. 8. One end comprises a tongue 36 whose outer edge 37 is obliquely disposed to an element of the cyl-. inder. Said tongue is provided with substantially parallel side edges 38 and 39 of about the same length, and substantially parallel to the lateral edges 40 and 41 of the skirt 35, thus forming the right angled shoulders 42 and 43 respectively. The other end 45 of the band forming this skirt 35 is formed to fit the end 36 just described. That is to say, said end 45 has two projecting parallelly' disposed 'tongues 46 and 47 adapted to fit the shoulders 42 and 43 of the other end of the band, with the recess 48 therebetween within which fits the tongue 36 of the other end 37 of the band. Thus it will be seen that the two ends of the band form an angular mortise and tenon joint and in this respect it will be observed that the edges 38 and 39 of the tongue 36 are adapted to closely fit between the tongues 46 and 47 of the other end of the band, but not to bind therebetween, so that at all times there may be a close sliding contact between these members. This skirt 35 is adapted to be placed around the main body portion 5 of the piston, the upper edge 40 of said band fitting against the shoulder 15, and the lower lateral edge 41 sitting against the shoulder 16. Further the entire skirt is adapted to overlie the spring rings 20 and is made of such a diameter that it will snugly contact the rounded points 31. The tension of each spring ring 20 is such that at each point 31 thereof said ring will tend to force the skirt 35 outwardly from the piston and against the inner circumferential wall of the engine cylinder, the shoulders 15 and 16 serving to'prevent the displacement of the skirt portion 35 longitudinally of the piston. The skirt portion is likewise provided with a plurality of obliquely disposed slits or apertures 50, the upper end of one vertically overlying the lower end of the next adjacent one as was the case with the slits 25 in the main body portion 5 of the piston. Further, the angularity of the slits 50 is substantially the same as the angularity of the slits 25,

method of securing the skirt portion 35 to the main body portion 5 of the piston. Stated in other words, with reference to Fig. 3 it will be seen that the upper .edge of the skirt portion 35 abuts against the shoulder 15 as heretofore disclosed, but the lower shoulder 16 is done away with, the surface 17 extending to the'lowermost edge of the main body portion 5 of the piston. In order that the skirt 35 may be retained in position, there is provided a plurality of lugs 55 integral with and outstanding from the surface 17. These lugs, are disposed below and adjacent the upper springring 20 and are adapted to fit correspondingly shaped apertures 56 provided in the skirt portion 35 of the piston. The lugs having substantiallysquare surfaces, there will be no possibility of the skirt portion coming away from the main body portion 5 of the piston. Another slight difference lies in the locking feature of the two ends of the skirt portion 35, which in this modified form consists of an L-shaped joint comprising the large tongue 58 of one end adapted to fit a correspondingly large angular recess 59 in the other end, thus making beside the large tongue 58 on the one end, asmall tongue 60 on the other end. The bottom of the skirt portion 35 extends to substantially the bottom of the main body portion 5 of the piston.

Referring to the modification shown in Fig. 4, the usual and common packing rings 4 are done away with, and the main skirt portion made of such width to very nearly cover the entire main body portion 5 of the piston. Stated in other words, the piston 1 of this modification is provided near its head portion 2 with a shoulder in all respects similar to the shoulder 15 of Figs. 1 and 2, and near the bottom of the main body portion 5 of said piston there is provided a shoulder 66 similar in all re spects to the shoulder 16 of said Figs. 1 and 2. Between these two shoulders 65 and 66 reposes the skirt portion 67 which is in all respects similar to the skirt portion 35 except as to its width and other corresponding dimensions. It has the same type of mortise and tenon provided on its ends for interlocking relationshi as did the skirt 35, and is further provlded with obliquely disposed slits or apertures 70 similar to the slits 50. The main body portion 5 of the piston of this modification is turned to produce the recessed surface 71 between the shoulders 65 and 66, and this surface is further reduced as at 72 i'mmedi- I lull ' annular groove 7 3 near the bottom of the piston, and with another groove 74 near the head 2 of the said piston, each groove to receive a spring ring 20. The walls ofthe main body portion 5 between the rooves 73 and 74 are apertured as by the slits 75 similar-in all respects, to the slits 25 in Figs. 1 and 2 except that the slits 75 are longer. With particular reference to Figs. 11 and 12, the purpose of the improved construction embodied-in this invention will be ap-' arent but maybe briefly stated as follows. he inner circumferential surface of the wall of the engine-cylinder 12 is always bored of a diameter greater than the outer circumferential dimension of the piston to operate in that cylinder as is well known. Therefore it-has been found' necessary to provide a piston with what have been termed packing rings, such as indicated at 4. However, these packing rings are customarily provided adjacent the head 2 of said piston, although it is known that a packing ring has been provided near the bottom of the piston similar inall respects to one of'the packing rings near the head thereof. -But either with or without this latter su plemental bottom packing ring, it has been found that the action of the piston in a cylinder is the same. In other words, the piston of an internal combustion engine, for example, is'capabIe of making many reciprocations per minute, and as clearly shown in Fig. 11, there is quite a perceptible vertical angle between the connecting link 8- and the central longitudinal axis assin through the wristpin 7 with which t e lin is associated. In other words, asthe engine crank 11 rotates, the lower end of the link 8 is moved laterally from side to side, and

with each movement, the position of the pis ton l is changed with respect. to the cylinder. For example, when the; link 8 is moved upwardly as seen in Fig. 111, the pistonwill be canted in the cylinder 12 with the result that it will assume'such a position as indicated in said figure. In such a case the packing rings 4 will not have a flat bearing contact with the surface 80 of the'cylinder, and as the engine crank 11 turns through 180 and the link 8 asso ciated therewith assumes a similar position on the left of the axis of the cylinder, the

.position of the piston will be reversed with the result that the packing rings 4 will have.

a different edge presented to the surface of the cylinder. With the continued changing of position of the piston, first one edge and then another of each packing ring 4 will be worn with the result that each ring will become rounded and eventually each ring will have a single point contact, thus caus ing a considerable leakage of the gases of combustion, as well as a leakage of oil into 'the combustion .chamber withthe resultant I formation of carbon therein, both of which are greatly to be avoided.

cumferential surface contact with the inner surface 80 of the cylinder as by'means of the spring rings 20 placed. above and below the wrist pin 7 of the piston. The result 10 With the. construction shown. in Fig. 1 4 wherein the preferred form of this invention.

is shown it will be obvious that the condition '80 and adapted to be expanded into total cir- I of this construction is that whe'nthe link 8 assumes its maximum oblique position, as shown in Fig. 12, and exerts a diagonal force upon the piston -1 as above described, I

the piston is preventedfromcanting in the cylinder by the relatively strong spring rings. 4

20 disposed between the expansiveskirt portion 35 and the mainbody portion 5 of said piston. In other words, the angular 'displacement of the piston will beso inappreciable as tobe practically nil.- Thus it will be seenthat the spring rings 20, by their novel andpeculiar shape perform a dual service, i

they uniformly press, atclose intervals, the

expansive skirt member 35 into total circumferential contact with the-cylinder wall 80, and at the same time kcepsaid skirt portion in substantially concentric or colUO axial relationship with the main body por- 1 tion of the-piston throughout the entire width of said skirt. Stated i-n"other words,

these rings exert an outward pressure against theskirt portion while at ther'same time they exert an inwardpressure' against the main body portion of the piston which is particularly advantageous in overcoming the conditions above described and partlcu- 1 larly illustrated in Fig. 11. Y

. .A great difiiculty in the tons, is that duringthe COIltlDllBdllSG 0 an engine, the pistons develop what is known as slap. That is to. say; 'p'stons have a great many reciprocations per minute and therefore the wear to which said pistons are subjected is not concentric. With particular reference to Fig. 11 thisfact is substantiated by the drawing, wherein it will be seen that the sde portions of thepiston, which might be said to be parallel to the wrist pin 7, take the wear rather than the other sides of the piston which are disposed in substantially the plane of the wrist pin.- Further the unevenly, with the result that the piston is ultimately whipped laterally thecylinder operation of isinner wall 80 ofthe cylinder likewise is worn during its reciprocation." This whipping from first one sidev to the other is termed slap and has every disastrous result, in unevenly-wearing the parts, and furtherit creates noise which is objectionable to the driver andother occupants of the automobile. By the employment of this invention, .on the other hand, this slap is counteracted and practically eliminated by the employment of the spring ring 20 between the walls of the piston, or in other words, be-

' tween the skirt portion 35 and the main, body portion of said piston. This is perfectly obvious from Figure 12,- wherein it will be seen that the skirt 35'is maintained in total surface contact with the inner wall 80 of the cylinder, and that the lateral movement of the piston in the cylinder is compensated for by the spring rings 20 to the extent that said movement is practically eliminated.

Therefore it will be seen that the skirt por-- tion prevents unequal cylinder wear .so that saidcylinder neednever be rebored thus giving longer life to the engine. Further it will be seen that said skirt takes up any cylinder wear that may havebeen produced by the piston in use rior to the substitution of the piston ma e in accordance with the present invention. In this respect it might be stated that when the skirt 35 I is worn it may be easily re laced by another at -a low ,cost thus making tor the economical upkeep of the engine. Further, skirts of different thickness can be .rovided for old or worn pistons and cylin ers, or cylinders which have been rebored, so that by this invention any type, or condition, or engine may be made more efiicient in operation.

It is well known that high temperatures are attained in internal combustionengines which causes the pistons to expand, but due toth'e use of this invention, the expansion and the main body portion of the piston,

which will not onl lubricate these parts but'will aid in cool ng the piston and thus reducing the high'temperature thereof.

. In operation and as well understood, oil is splashed from the engine crank case, or otherwise deposited, on the inner surface 80 of each of the engine cylinders. As the piston reciprocates inthe cylinder, and due to the fact that the cylinder'isof a larger diameter than said piston, the rings 4 and skirt her, or that region above the piston. 'aid in the distribution of the oil over the avaaae portion 35, will distribute the oil'to the entire surface of the cylinder. However, it is greatly to be desired that said oil not pass above the head 2 of the piston, and therefore itis the purpose of the rings 4 to prevent the oil reaching the combustion 011.51%-

surfaceof the cylinder, the slits 50, illustrated in Fig. 3, and the slits 70, illustrated in Fig. tare provided in the skirt portion 35 and-67 respectively. As the oil reaches these slits it is entrapped therein, with the result that each slit becomes an oil reservoir, and due to the oblique disposition of saidslits, the oil is enabled to travel circumferentially and'thus become deposited on a larger area of the cylinder wall than if the. slits were omitted.

In addition to this, the oil from each slit in the skirt of the piston can pass therethrough and thus lubricate the inner sur-- face of the skirt, the spring rings 20, and eventually'pass to the depression 23 or 72 which is associated with the end of the wrist pin bore 22. When the oil has reached this depression, it will then find its wayinto the wrist pin bearing and lubricate the same. Any excess accumulation of oil will be passed through the slits 25 or 75 which are provided in the main body portion 5 of the piston, thus reaching the interior of the piston Where said oil may drop under the action of gravity to the engine crank case, or other source of supply, to be again used as above described. 7

A particular advantage of the construc- Mill tion disclosed herein lies in the fact that the skirt portion of the piston insures the formation of a wide film of lubricant between said skirt and the inner circumferential wall of the cylinder, which film due to its I width, will ofl'er a comparatively great reslstance to the pressure of the gases in the chamber above the head 2 and so prevent the diminution of said pressure In the case of an internal combustion engine, said Wide film of lubricant will prevent the escape of the hot gases of combination from said chamber into the lower portion of the cylinder and engine crank case, and so prevent the burning of the oil therein.

Another important feature of this invention is that the skirt portion covers the wrist pin bearings and thus prevents the ends of the wrist pin from reaching the I cylinder wall and scoring the same during the reciprocations of the piston.

Summarizing the foregoing, it will therefore be seen that there is provided a piston provided with a head 2, a main body portion-5, and a wrist pin bore 22 disposed in a hollow cylinder 12 of a reciprocating engine which maybe of the internal combustion type or other form. Further, there is provided an expansible means comprising the skirt 35, which is associated with the main body portion of the piston, which is adapted to cover the wrist pin bores and to circumferentially contact with the wall of the cylinder. Lastly, there is provided a spring means comprising the polygonal ,shapecl ring 20 having a plurality of arcuate sides and associated points 31, each ring being disposed adjacent the wrist pin bore, said rings-to automatically insure total circumferential surface contact between the skirt and the, cylinder wall through said points 31. Further, it will be observed that the slits in the skirt 35 provide a means for spreading the lubricant over the cylinder Wall as well as the surface of said skirt, and that these slits are further adapted to transmit the lubricant to the spring rings 20 and to each wrist pin bore 22, while the slits 25 in the main body portion 5 of the piston provides a means to re- .turn the transmitted lubricant to the source of supply. 7

I It is obvious that those skilled in the art may vary the details of construction as well as the arrangements of parts without departing from the spirit of the invention and therefore it is not desired to be limited to the foregoing disclosure except as maybe required by the claims.

What is claimed is Y 1. In a reciprocating engine the combination of a hollow cylinder adapted to receive a lubricant on the inner wall thereof from a source of supply; a piston provided with a head, a main body portion and a wrist-pin bore disposed in said cylinder; means associated with said piston adapted to circumferentially contact with said cylinder; relatively spaced means between said contact means and said piston to space the same .dur-.

ing its reciprocations from said cylinder; and means in said contact means to transmit said lubricant to said wrist-pin bore and said spacing means, while spreading the same over the surfaces of said contact means and said cylinder wall.

2. In a reciprocatin engine the combination of a hollow cylin er adapted to receive a lubricant on the inner wall thereof from a source of supply; a piston provided with a head, a main body portion and a wrist pin bore disposed in said cylinder; means associated with said piston adapted to circumferenti'all contact with said cylinder wall; means to msure said circumferential contact;

and means to spread said lubricant over said cylinder walland the surface of said first named means contactin therewith, said means adapted to transmit said lubricant to said second named meansand to said wrist pin bore.

3. In a reciprocating engine the combination of a hollow cylinder adapted to receive a lubricant on the inner wall thereof from a source of supply; a piston provided with a head, a main body portion and a wrist pin bore disposed in said cylinder; means asso-.

ciated with said piston adapted to circumferentially contact with said cylinder wall;

means to insure said circumferential con-- tact; and means disposed in said first named means to spread said lubricant over said cylinder wall and the surface'of said first named means contacting therewith.

4. In a reciprocating enginethe combination of a hollow cylinder adapted to receive a lubricant on the inner wall thereof from a source of supply; a piston provided with a head, a. main body portion and awrist pin bore disposed in said cylinder; means associated with said piston adapted to'circumferentially contact with said cylinder wall; means to'msure said circumferential contact means to spread said lubricant over said cylinder wall and the surface of said first named means contactin therewith, said means adaptedto transmit said lubricant to said second named means and to said wrist tion of a hollow cylin er adapted to receive a lubricant on the inner wall thereof from a source of supply; a piston-provided with a head, a main odyportion and a wrist pin bore disposed in said cylinder; means associated with said piston adapted tocircumferentially contact with said 0 linder wall; means to insure said circumf drential contact; means disposed in said first named means to s read said lubricant .over said cylinder wal and the surface of said first named means contacting means adapted to transmit said lubricant to said second named means and to said wrist in bore; and means disposed in the main y portion of said piston to return the transmitted lubricant to the source of supply. 4

In testimony whereof I aflix my signature.

THOMAS J. LEVEY.

therewith, said 

